So whenever you guys race someone you ask them 6 mt or Auto? and if their auto you don't race because its not "fair".lol

So your saying when i race M33 i will lay a smack down because dct can over come 90 more horses? So if we know the outcome already why even race.

AA does reduce redline btw.

Not exactly , us racing from let's say 80 mph will yeild very different results and that's where DCT's advantage falls off , Dct is ideal in the first 4 gears , after that 6mt wakes up and is ideal ..
When we run we'll do different runs so everyone can see the difference at certain gears and speeds ..

Here's a video PG put together for me just to demonstrate what happens to near equal cars:
...
So no matter how you look at it, the 6MT had every advantage in its favor. Yet in spite of it, look what happens.

In the race above, the DCT demolishes the 6MT in every way possible. In spite of a horsepower and density altitude disadvantage, the DCT beats the 6MT by 15.6+ car lengths, 1.364 seconds, and 8.955 MPH. So the next time you see somebody try to compare a DCT to 6MT and tries to tell you they are equal, just show them this video.

For more proof, look at this vBox Racer video. The last race in this video is Drew's car vs. mine racing 60-130 MPH. Even though I have more HP that Drew, I get slaughtered in the race just like Zim got slaughtered in the drag race above.

Wow not even sure where to start here. In short this is pretty much all incorrect. It looks like we will probably get way off topic but I can't let this rubbish slide.

Assuming good traction, good launch, etc., power to weight is what determines ET and trap speeds. I don't often side with Sticky but he is essentially right here. Everything else is a much smaller factor.

Sure if you have a crappy driver in a MT who takes 0.6 seconds to shift, yes this will hurt your ET and trap by quite a lot but a fast shifter can shift a MT in closer to 0.25-0.3 seconds and we should assume this is happening to give a MT a fair shake.

I've been a strong and long term proponent of DCT over MT for performance reasons. It does matter but it does not matter nearly as much as you and your referenced info claim. According to both simulations and empirical test results DCT (in a stock M3) is good for about an equivalent of 15-20 hp. That in turn is only good for a few tenths in the 1/4 mi.

The advantage of DCT is almost entirely due to shift speed advantages, not gear ratio differences. This also has been proven out with simulation quite well. Where DCT gear ratios shine, that is not related to drag racing, is coming out of a corner at an equal speed to a MT in 2nd or 3rd gear. The overall ratios are quite a bit higher and thus the DCT will come out of corner much harder and pull ahead.

The cars that were compared in this "re-enactment" simply DO NOT have anywhere close to the same power. I don't care what the dynos say, different dyno, different conditions, different days, different tunes, different operator, etc. How many differences do you need? The DCT car in this case had substantially more power, period. If the two cars actually had 586 and 594 hp respectively their 1/4 times would be within 0.3 sec ET and 3.5 mph trap, accounting for the DCT advantages and assuming a 0.3 second shift time.

It takes about a 75 hp difference and the DCT->MT disadvantage to provide a true 9 mph trap speed difference.

Even a really terrible shift time of 0.6 s in the MT would only account for about half of the observed ET differences here. Again... apples to oranges, period.

Have a look at some stock M3 quarter mile results differences between DCT and MT. Here we have very high confidence that both cars will be making VERY close to the same power.

If you really think this is a true apples to apples comparison of DCT vs. MT then I have some great business ideas centered around selling sand to some Arabs that we should really discuss in detail in person.

Wow not even sure where to start here. In short this is pretty much all incorrect. It looks like we will probably get way off topic but I can't let this rubbish slide.

Assuming good traction, good launch, etc., power to weight is what determines ET and trap speeds. I don't often side with Sticky but he is essentially right here. Everything else is a much smaller factor.

Sure if you have a crappy driver in a MT who takes 0.6 seconds to shift, yes this will hurt your ET and trap by quite a lot but a fast shifter can shift a MT in closer to 0.25-0.3 seconds and we should assume this is happening to give a MT a fair shake.

I've been a strong and long term proponent of DCT over MT for performance reasons. It does matter but it does not matter nearly as much as you and your referenced info claim. According to both simulations and empirical test results DCT (in a stock M3) is good for about an equivalent of 15-20 hp. That in turn is only good for a few tenths in the 1/4 mi.

The advantage of DCT is almost entirely due to shift speed advantages, not gear ratio differences. This also has been proven out with simulation quite well. Where DCT gear ratios shine, that is not related to drag racing, is coming out of a corner at an equal speed to a MT in 2nd or 3rd gear. The overall ratios are quite a bit higher and thus the DCT will come out of corner much harder and pull ahead.

The cars that were compared in this "re-enactment" simply DO NOT have anywhere close to the same power. I don't care what the dynos say, different dyno, different conditions, different days, different tunes, different operator, etc. How many differences do you need? The DCT car in this case had substantially more power, period. If the two cars actually had 586 and 594 hp respectively their 1/4 times would be within 0.3 sec ET and 3.5 mph trap, accounting for the DCT advantages and assuming a 0.3 second shift time.

It takes about a 75 hp difference and the DCT->MT disadvantage to provide a true 9 mph trap speed difference.

Even a really terrible shift time of 0.6 s in the MT would only account for about half of the observed ET differences here. Again... apples to oranges, period.

Have a look at some stock M3 quarter mile results differences between DCT and MT. Here we have very high confidence that both cars will be making VERY close to the same power.

If you really think this is a true apples to apples comparison of DCT vs. MT then I have some great business ideas centered around selling sand to some Arabs that we should really discuss in detail in person.

Ugh...

You do make some good points, but I think you're just a bit too confident in your assertions.

So far with boosted E9X M3's, when you look at Vbox results, comparo runs, trap speeds, etc, the DCT is superior in straight line acceleration, that's just the way it is, it appears just about everybody, especially those with actual experience, acknowledge this to be the case.

The 6MT and DCT cars in that vid DID make similar WHP on a Dynojet, when comparing different Dynojets it is quite rare that you will get a huge difference in WHP, that's what CF's are for. I do agree that a 6MT with more traction would be a better comparison but for you to overly assert that they aren't making the same whp is rubbish.

You say the DCT is only good for 15-20whp?

Then how do you explain a 366whp DCT trapping 116 and a 500+whp Supercharged 6MT trapping 119, same day, same track?

When you take the traction factor out of it -

How do explain the .7 - 1 second difference between supercharged 6MT's and DCT's 60-130, even when the 6MT's are making more power?

How do you explain the 6MT SC'd Stroker 613whp being .5 -.7s slower than a 570whp and 586whp DCT M3?

How do you explain a DCT making 570whp vs. a 6MT making 590whp, same kit, same dyno on the same day as well produce vastly different results in comparo runs, the DCT was MUCH faster.

How do you explain on the same stretch of road, a Stage 3 6MT @ 640-660whp doing 60-130 in 6.9s vs. a DCT Stage 2 @ 586WHP doing 60-130 in 7 flat and 6.8s, even with 60+whp less the DCT was still faster.

I get what you're trying to say, we're just not seeing that in the results so far.

Wow not even sure where to start here. In
short this is pretty much all incorrect. It looks like we will
probably get way off topic but I can't let this rubbish slide.

Assuming good traction, good launch, etc., power to weight is
what determines ET and trap speeds. I don't often side with Sticky
but he is essentially right here. Everything else is a much
smaller factor.

Sure if you have a crappy driver in a MT who takes 0.6 seconds
to shift, yes this will hurt your ET and trap by quite a lot but a
fast shifter can shift a MT in closer to 0.25-0.3 seconds and we
should assume this is happening to give a MT a fair shake.

I've been a strong and long term proponent of DCT over MT for
performance reasons. It does matter but it does not matter nearly
as much as you and your referenced info claim. According to both
simulations and empirical test results DCT (in a stock M3) is good
for about an equivalent of 15-20 hp. That in turn is only good for
a few tenths in the 1/4 mi.

The advantage of DCT is almost entirely due to shift speed
advantages, not gear ratio differences. This also has been proven
out with simulation quite well. Where DCT gear ratios shine, that
is not related to drag racing, is coming out of a corner at an
equal speed to a MT in 2nd or 3rd gear. The overall ratios are
quite a bit higher and thus the DCT will come out of corner much
harder and pull ahead.

The cars that were compared in this "re-enactment" simply DO
NOT have anywhere close to the same power. I don't care what the
dynos say, different dyno, different conditions, different days,
different tunes, different operator, etc. How many differences do
you need? The DCT car in this case had substantially more power,
period. If the two cars actually had 586 and 594 hp respectively
their 1/4 times would be within 0.3 sec ET and 3.5 mph trap,
accounting for the DCT advantages and assuming a 0.3 second shift
time.

It takes about a 75 hp difference and the DCT->MT disadvantage
to provide a true 9 mph trap speed difference.

Even a really terrible shift time of 0.6 s in the MT would only
account for about half of the observed ET differences here.
Again... apples to oranges, period.

Have a look at some stock M3 quarter mile results differences
between DCT and MT. Here we have very high confidence that both
cars will be making VERY close to the same power.

If you really think this is a true apples to apples comparison
of DCT vs. MT then I have some great business ideas centered
around selling sand to some Arabs that we should really discuss in
detail in person.

Ugh...

Swamp, this is one of those times you should have actually done
some of those simulations that you're talking about to see what
happens in the results. I just did, and it seems to match these
actual street results quite well. If fact, I'd say they match
perfectly well.

I've looked at many 6MT vBox graphs, and 0.6 seconds is the
fastest shift speed I've ever seen. Most are about 0.7, and some
are 0.8 seconds. That's measured from the time long-acc drops, to
the time it returns. So that's the amount of time from clutch in,
to clutch out and full engagement.

Since you're a CarTest fan, you'll appreciate looking at the two
charts below. As you know, you can input actual dyno charts into
CarTest. If you do this, then these are the results. The same
exact car model was used for each car, both listed at 3704 pounds,
and 6MT using a 0.6 second shift time -- which is the fastest I've
ever seen on a vBox file. The DCT used 0.05 seconds shift time.
The first chart compares the same dyno chart from an ESS VT2-600
(517whp) in both DCT and 6MT.

The graph above shows 0.61 seconds difference, and 8.53 MPH
difference in the 1/4 mile, along with 1.2 second difference
60-130 MPH (yes, a whopping 1.2 seconds difference 60-130 MPH).
If you change the shift speed to 0.4 seconds (seems impossible
based on actual collected vBox data), the results become as
follows: 0.41 seconds difference and 6.27 MPH difference in the
1/4 mile, along with 0.95 second 60-130 time. You'll notice that
CarTest predicts an additional 2.26 MPH trap speed difference
simply by changing the shift speed by 0.2 seconds.

Now, let's do the same thing using the actual dyno charts from
DLSJ5 (DCT @ 586whp) and M33 (6MT @ 594whp). Here's the CarTest
results below:

As you can see, using 0.6 seconds shift speed for the 6MT, it
loses in the 1/4 mile by 0.67 seconds and 9.91 MPH in the 1/4
mile, and 1.68 seconds 60-130 MPH. Then if we reduce the 6MT
shift speed to 0.4 seconds (again...a seemingly impossible task
based on actual collected vBox data), the 6MT loses by 0.46
seconds and 7.48 MPH in the 1/4 mile, and loses by 1.42 seconds
60-130 MPH.

Swamp, there is quite a bit of real life data collected in vBox
files. Those files show the 6MT is quite a bit slower than the
DCT for similar configurations. For whatever reason, you're
chosing to ignore it and substitute your own. You love CarTest
and talk about all of these simulations, but this is one case
where you should have used it and seen the results for yourself.
The CarTest simulations back up exactly what is one those vBox
files and that "re-enactment" referenced above.

Feel free to download the actual dyno charts from DLSJ5 and M33
from the Dyno Database, imput them into CarTest, and publish your
own versions based on these same dyno charts. For your reference,
here's the values used in CarTest for each vehicle. If you can
spot something wrong, please point it out so it can be fixed and
simulations re-run. But only do that if you are convinced that
something is so egregiously wrong that you think it will
significantly change these results -- which also seem to match
real life quite well.

I donīt belive that the difference is so big as the Vbox race above claims in real life.
We did some testing at a M5board event with my 335 DCt vs 335 manual.
We had the same settings on the procedes and similar mods, take a look .The white car is my old car with DCT, Big tom is driving the manual, he shifts real fast.

Per you have to realize one thing when comparing a turbo 335 to a supercharged M3 they are very different in power delivery for starters ,
300 to 800 rpm can net you 60 to 120 whp (ballpark) between shifts where as the turbo will net you 20 40whp .
The other factor is gearing

take a look what i have to do to pass forum member ERM ( ricky ) on our way to ATCO
[u2b]http://www.youtube.com/watch?v=srJKTVfCbnQ&hd=1/U2B]

PG caught a really small mistake in the CarTest data posted last
night. He noticed that 4th gear listed on the DCT in the CarTest
data was incorrectly set at 1.29:1 instead of 1.39:1. So he
corrected the gear ratio and re-ran the simulations. No real
difference -- only about 0.01 seconds in the 1/4 mile, and 0.02
MPH in the 1/4 mile. The charts posted above are now updated with
the corrections -- no need to repost them again, or give a new set
of numbers since the differences are insignificant.

Quote:

Originally Posted by per

I donīt belive that the difference is so big as the
Vbox race above claims in real life.
We did some testing at a M5board event with my 335 DCt vs 335
manual.
We had the same settings on the procedes and similar mods, take a
look .The white car is my old car with DCT, Big tom is driving the
manual, he shifts real fast.

This is not a good comparison and unfortunately doesn't prove
anything. The DCT in the 335 has a different 2nd gear, and the
final drive ratio is totally different. The M3's in the video
have double the WHP as the 335's. The comparison is about as
apples to oranges as you can get -- the only links between them
are the letters "BMW" and "DCT" -- everything else is different.

The vBox race above is NOT a simulation -- it's the actual car's
performance according to the vBox, but animated into a video.
What you see in the video, is exactly what would have happened if
those two cars met on the pavement. If you have vBox files of
your M5board event between these two cars, then send them to me,
and I'll have PG make them into a video as well.

PG told me that on his next vBox Racer video, he'll compare a
Gintani Stage-3 low comperssion motor against Drew's ESS VT2-625.
This comparison will be interesting because it should really give
the critics much less reason to doubt. Both cars were dyno'd at
the same dyno on the same day only hours apart; and their vBox
files come from the same exact stretch of road. So the critics
can't complain about different dynos, different weather or
different days on the dyno, or a different road. We already know
from DLSJ5 that he beats the Gintani stage-3 that has 60+whp more
but is 6MT. But until we see the video, we won't know how many
car lengths the DCT with 60whp less beat the Gintani Stage-3 6MT.

I'll start here and reply to the next (from img) when I have a bit more breathing room with work...

Quote:

Originally Posted by DLSJ5

You do make some good points, but I think you're just a bit too confident in your assertions.

So far with boosted E9X M3's, when you look at Vbox results, comparo runs, trap speeds, etc, the DCT is superior in straight line acceleration, that's just the way it is, it appears just about everybody, especially those with actual experience, acknowledge this to be the case.

We agree here, DCT provides improved acceleration, it is due nearly entirely to shift time, not gear ratios differences. We simply disagree about the size of the benefit.

Quote:

Originally Posted by DLSJ5

The 6MT and DCT cars in that vid DID make similar WHP on a Dynojet, when comparing different Dynojets it is quite rare that you will get a huge difference in WHP, that's what CF's are for. I do agree that a 6MT with more traction would be a better comparison but for you to overly assert that they aren't making the same whp is rubbish.

There are simply way too many variables here as I have covered. Fact of the matter is very simple. Cars with the same peak hp time and trap (in an apple to apples comparison) at very close to the same numbers, period. If the numbers are radically different but drivers and traction and the like are similar, then THE only logical explanation is a power difference. There is not too much debatable on this point.

Quote:

Originally Posted by DLSJ5

You say the DCT is only good for 15-20whp?

If you want to think of a hp equivalent for DCT, based on a stock 414 hp M3, and when looking at 1/4 mi times/trap, yes this is the difference. Both test and simulations back up this claim. In many cases the results are so close that other factors even overcome the differences. Have a look here at this performance "database" of stock M3 performance results.

Quote:

Originally Posted by DLSJ5

Then how do you explain a 366whp DCT trapping 116 and a 500+whp Supercharged 6MT trapping 119, same day, same track?

There are only about a dozen explanations. But the essense of it is that it is an apples to oranges comparison where BOTH cars did not each reach there best possible time and trap.

Quote:

Originally Posted by DLSJ5

When you take the traction factor out of it -

How do explain the .7 - 1 second difference between supercharged 6MT's and DCT's 60-130, even when the 6MT's are making more power?

Not enough information to make any guesses on this case.

Quote:

Originally Posted by DLSJ5

How do you explain the 6MT SC'd Stroker 613whp being .5 -.7s slower than a 570whp and 586whp DCT M3?

How do you explain a DCT making 570whp vs. a 6MT making 590whp, same kit, same dyno on the same day as well produce vastly different results in comparo runs, the DCT was MUCH faster.

How do you explain on the same stretch of road, a Stage 3 6MT @ 640-660whp doing 60-130 in 6.9s vs. a DCT Stage 2 @ 586WHP doing 60-130 in 7 flat and 6.8s, even with 60+whp less the DCT was still faster.

I suppose you can come up with case after case of seeming exceptions to the rules. I am pretty confident that DCT absolutely can not make up a 60 hp defecit in a 60-130 run. I will run some more sims to look into this case.

Also do note: I ran quite a few simulations to form/validate/back up some of the claims I made in my prior post. The basics I did long ago but added some work right when posting. I will have to put those together and also reply to the simulation based post response from img.

Perhaps we should take this offline to another topic? I think it is a great topic for a totally separate thread. I'm a huge proponent of DCT, always have been. However, there is simply too much being ascribed to it here. It is not magic, it just shifts fast. We should all not ruin your cool engine build thread with this useful debate/discussion.

This is not a good comparison and unfortunately doesn't prove anything. The DCT in the 335 has a different 2nd gear, and the final drive ratio is totally different. The M3's in the video have double the WHP as the 335's. The comparison is about as apples to oranges as you can get -- the only links between them are the letters "BMW" and "DCT" -- everything else is different.

Ugh, I say let's move to a different thread and then I get sucked back in.

Absolutely disagree. This is much more apples to apples than the cases you guys are coming up with to support your claims. The MT and M-DCT in the M3 have completely different total effective gear ratios (gear ratio x final drive). But ultimately that does not matter (partly as you saw with your typo gear ratio error!). However, in the 335 case, you are at least guaranteed to a factory tolerance level that the cars ARE putting down identical peak powers. This is something very poorly controlled and lacking in all of the dynojet and other dyno work. You should know as well as any (and as PG himself has pointed out) dynos can be subject to large manipulations or errors. I'm not calling out anyone in particular, owners, dyno owners, etc. It just is nowhere near factory repeatable and thus CAN be subject to large errors.

The DCT is definitly faster but a god driver could reduce the dct advantage a lot, take a look at the shifts in the movie above, he hardly lose any ground at all.
Both 335 cars have app 370-380 whp 200 less than a ess vt625 but still...
We will probably have the opportunity to test a G-power SK2+ (9psi) DCT vs my Vt625 i a month or so, then i have to decide if i have to change the car but keep the ess kit or not,depending on the outcome

There are simply way too many variables here as I
have covered. Fact of the matter is very simple. Cars with the
same peak hp time and trap (in an apple to apples comparison) at
very close to the same numbers, period. If the numbers are
radically different but drivers and traction and the like are
similar, then THE only logical explanation is a power difference.
There is not too much debatable on this point.

Swamp, "we" keep talking from real life using a combination of
actual dyno charts input into CarTest, shift times from vBox
entered into CarTest etc., then simulating the results. We are
also talking our own Mexico runs that have the same results. So
far, the CarTest results perfectly match the real life results
we've seen. You haven't offered any simulations or any real-life
data other than stock cars in controlled environments with
professional drivers. When you double the horsepower, I'm telling
you that everything changes. I'm sure you're mulling over the
data posted above and looking for something wrong. It will be
interesting to see what you come up with.

BTW, I don't think the accepted science of trap speed isn't as
universally accepted as you think. I was at an NHRA drag race
last year and asked one of the top fuel drag racers this exact
question. At first he laughed and then added that everything from
shift speed to gear ratios affects the trap speed. So just to
satisfy my own curiosity, I ran CarTest simulations on a bone
stock DCT modifying nothing but the final drive ratio from 1.50 to
3.62. CarTest predicts a 7MPH trap speed difference between these
two ratios. How is this possible if gears don't make a difference
in trap speed?

We can start up this debate when DLSJ5 posts the vBox Racer video
of him racing Tightie's car.

The DCT is definitly faster but a god driver could reduce the dct advantage a lot, take a look at the shifts in the movie above, he hardly lose any ground at all.
Both 335 cars have app 370-380 whp 200 less than a ess vt625 but still...
We will probably have the opportunity to test a G-power SK2+ (9psi) DCT vs my Vt625 i a month or so, then i have to decide if i have to change the car but keep the ess kit or not,depending on the outcome

This will be interesting to see ! Keep us posted btw per what did your car put down ?

The DCT is definitly faster but a god driver could reduce the dct advantage a lot, take a look at the shifts in the movie above, he hardly lose any ground at all.

Yes the manual driver would have to be "god" like to be as fast as the DCT J/k

I have to find the vid of Drew (i think that is name) when he was in mexico with the vette, GTR and 458. The vette lost out big time on the shifts vs the other 3 DSG cars. You see the vette lose ground every time he shifted.